Reticulocytes are late juvenile erythrocytes that have not fully matured after the nucleus has been removed. The reticulocyte count is expressed as the percentage of reticulocytes in the total number of red blood cells in the peripheral blood, and its normal range is 0.5%-1.5%. A high reticulocyte count reflects the hematopoietic capacity of the bone marrow. A high reticulocyte count indicates vigorous hematopoiesis, while a low reticulocyte count indicates low hematopoiesis. A high reticulocyte count is common in cases of acute blood loss, as the number of red blood cells in the peripheral blood is insufficient after acute blood loss, and the bone marrow will release the reticulocytes that are not fully mature through regulation to play a compensatory role. High reticulocytes are also seen in iron deficiency anemia and megaloblastic anemia, where the reticulocyte count increases after treatment has taken effect.